Stern frame with balanced rudder for ships



March 5, 1929. H s 1,704,434

s'rsrm mum WITH BALANCED mm FOR smrs Filed April 1, i927 2 Sheets-Sheet 1 s 47 Jzwerzzor:

March 5, 19 29. I H. HASS 1,704,434

STERN ml! WITH BALANCED RUDDER FOR SHIPS Filed April 1, 1927 2 Sheets-Sheet 2 Patented Mar. 5, 1929.

UNITED STATES PATENT OFFICE.

ms mes, or BERGEDOBI, NEAR manna, emer STERN FRAME WITH BALANCED BUDDEB 1'08 Application fled April 1, 1927, Serial No. 180,210, and in eelan December 4, 192s.

My invention relates to an improved stern frame with a balanced rudder for use in connlection with ships, particularly screw-driven s 1 s. 5 l alanced rudders as hitherto constructed are usually mounted on a comparatively short, separate frame or post located in the rear of the propeller post and which does not extend over the full length of the rudder, the arran ement being such that the u per part of t e rudder is pivotally mounte on dg'eonswhilst a part of the, body of the ru der extends towardsthe hull of the ship below the rudder frame or post.

It has also been suggested heretofore to interconnect the rudder post with the'propeller post at the bottom thereof or by means of a bottom member so that the two posts form a sin 1e piece or frame, the rudder being pivota ly supported in particular bearin s provided for the purpose in the frame. he former construction and arrangement are objectionable for the reason that the balanced rudder is supported on or over a comparatively short extent only and the short rudder post necessarily must be bulky and powerful in order to stand the stresses andstrains inherent to a rudder of the stated type. The latter construction and arrangement heretofore sug ested are objectionable for the reason that t e provision of particular bearings in the frame for supporting the rudder body involves an excessive resistance of the ship to propulsion due to the formation of eddies.

The object of my invention is to remedp these defects and with'this object in view provide a stern frame forming a-structure which is closed in itself so as to e of eminent 40 strength and rigidity, and which is shaped at the same time with a view to avoid any resistances that might give rise to the formation of eddies. In a modification I even utilize the rudder for causing the, current of water helically repelled from the propeller,

to flow off in a direction parallel or approximately parallel as far as this is attainable,

to the axis of the propeller shaft, whereby the efficiency of the propeller will be greatly increased.

With the above recited and other objects in view, reference is had to the following specification and drawings in which there are exhibited several exam however, intended as a limitatipn upon the les or embodi-' ments of the inventlon WhlC are in. no way,

scope of the appended claims as it is to be clearly understood that variations and modifications which fairl fall within the true scope of the said clalms may be resorted-to when found expedient. g

In the accompan ing drawings formin a part of this speci catlon and showing %or pur oses of exemplification, as above stated, pre erred forms and manner in which the invention may be embodied and practised Q Figure 1 illustrates in side elevation a thereof Fi re 6. is an enlarged sectional view on plane VIVI of Figure 5; and

Figure 7 is. a sectional view. similar to Figure 2, representing a further modification of the rudder.

Where desirable the same reference sym-- bols are used in the different figures to denote corresponding parts.

Referring to Figures 1 and 2, the balanced rudder 1- is mounted on or about a post 2 integral with the propeller frame 3 to fornia strongand rigid closed structure. It will-be seen in Figure 1 that the rudder post 2 is connected at the top with the frame 3 by a bridge piece 4 and at the bottom by a base piece 5. In accordance with the present invention the rudder is shaped to form a so-called stream-line body which completely surrounds or encloses the post 2.

In order to enable the rudder to be angularly dis laced or turned to a suflicient degree wit out causing the metallic plates rming the skin 60f the rudder to come in contact with the post 2, the latter. is located so as to concide with the axis A-A of the rudder. Preferably the rudder may be pivotally mounted on the frame by means of gudgeons 7 and 8. To this end the rudder may be equipped with an eye for engagement with the-gudgeon 8 or a separate vertical rodsuch as 10, see Figure 1, may be ca y through the rudder and having an eye emlployed, the said rod 10 extending verti- 9 at its bottom and in engagement with the gudgeon 8. As for the purpose of inserting or removing the rudder, when required, the lowermost part of the post 2 necessarily must be undercut or bent inwards, as at 11 in Figure 1 and it will be of advantage to cut out the adjacent part of the sheet metal formin the skin 6 of the rudder, on the line indicated by 12 in Figure 1 and to substitute for the cut out portion a stationary sheet or plate structure 13 which is to be rigidly connected with the post 2 and the base piece 5'of the frame 3 so as to not follow the movements of the balanced rudder.

The body of the rudder comprises, as usually horizontal arms or struts 14 adapted to support the metallic sheets forming the skin 6, which are firmly connected with the said arms or struts 14 by means of rivets or bolts. Care is to be taken that the skin 6 be prevented from coming in contact with thepart 2, when the rudder is shifted into the one or the other extreme position, and

to this end the rudder must be given a sectionalarea of sufficient width at those places where the skin is in close proximity to the post, so that there will always be a free gap between the post and the skin.

In some cases it will be advisable to give the rudder post 2 a cross-sectional area as shown in Figure 2 where or so that the longer sides of the rectangular area denoted by 2 are situated perpendicular to the longitudinal axis of the ship, whereb a very strong and durable construction of the post will be obtained. The frontal part 6 of the skin 6 may be connected with the rear part thereof in any suitable manner, in the embodiment shown in Figure 2 the two parts are interconnected by overlapping as at 6 and reinforcin plates or sheets 15 are provided in the front part; 6. The bod of the rudder may be divided on a longitu inal vertical plane going through the center thereof for the purpose of ensuring ready access tovthe bearing and rendering the rudder detachable from the post 2, I prefer,

however, to divide the rudder body on a' plane rectangularly intersecting the said longitudinal plane, as above intimated.

In the embodiments shown in Figures 3 to 6 the gudgeons 7 and 8 are dispensed with and bearings 16 are provided in lieu thereof in the body of the rudder, the said bearings 16 being adapted to enclose and fit about corresponding bearing surfaces provided on the post 17 which is rigidly connected or integral with a base piece 18 of the propeller frame 19 so as to form therewith a closed frame structure, just as hereinbefore described with reference to the corresponding parts 5 and 2 of Figure 1. Further the propeller frame shown inFigure 3 is rovided with guiding surfaces 20 and 21 w ieh are shaped and adapted to impart a preliminary torsion to the current of water flowing towards or into the propeller screw, so that the current of water will be discharged from the propeller screw in a direction approximately parallel to the axis of the propeller shaft prior to its striking upon the vertical front edge 22 of the rudder. Thus owing to the stream-line shape or formation of the body of the rudder the current of water repelled by the propeller, will flow in fore-to-aft direction without giving rise to the formation of prejudicial eddies.

In the modification illustrated in Figures 3 to 6 the metal plates constituting the skin or plating of the rudder are interconnected by means of arms or struts 24 which preferably comprise a plate 25 with lateral flanges 26 and which are shaped to form the aforesaid bearings 16 co-operating with hearing surfaces on the post 17, as will be clearly seen in Figure 4. In this modification the body of the rudder is likewise divided on a plane BB, see Figure 4, situated vertically to the fore-and-aft line of the rudder, the arms or struts 24 possessing a separate frontal or fore part 27 and the bearing 16 being correspondingly split or divided. The two parts thus formlng an arm or strut 24 are firmly connected with each other in any appropriate manner such as by bolts 28 or the like.

In the modification of the balanced rudder shown in Figures 5 and 6 the two parts- 1 and 1*, see Figure 1-are interconnected in a different manner. The rear or aft part of the rudder body or the arms thereof are provided with bifurcated ends or projections and the front or fore part thereof is provided with single pro ections 31 adapted to engage between the shanks 30 of the forked part for interconnecting purposes, cotters 29 engaging in suitable holes of the intermeshing projections serving to ensure an efiicient, detachable connection between the parts. 1

Figure 7 illustrates a further modification of the rudder body in which the parts thereof extendin below the propeller shaft and above the s aft are bent out of the longitudinal median plane of the rudder so as to project towards the propeller in different directions, for the purpose of utilizin the lateral surfaces of the rudder for guiding and directing the current of water helically repelled by the propeller, in a manner that the single water threads thereof will be given a tendency to flow approximately parallel to the axis of the propeller shaft, whereby the eflieiency of the propeller screw will be greatly enhanced.

To this end the two lateral surfaces 32 and 33 of the upper half of the body of the rudder are differently shaped or curved and the corresponding surfaces 32 and 33'- of the part of the rudder body below the axis of the propeller shaft are of a similar configuration but in opposed relationship, as will be readily understood on inspection of Figure 7 The post 2 is enclosed within the rudder body and may be widened to the same cross-sectional area as described with reference to Figure 2, in order to increase the strength and rigidity thereof.

The provision of a dividing joint in the rudder body preferably vertically to the length thereof, or in other words, a rudder body consisting of two individual parts adapted to be disconnected, when required, as herein described and shown, involves valuable advantages. For the rudder can be easily dismounted without interfering with the rudder post, and this may be done simply by removing the detachable front part thereof after the rudder has been turned fully to port or starboard, whereby a further advantage is obtained inasmuch as sufficient space will be secured thereby for the removal of the propeller screw without requiring the rudder post to be removed or the propeller-shaft to be withdrawn inwards. This advantage is the more important as the usual guiding or directing surfaces as hitherto constructed in the rear of the pro-, peller prevent the latter from being removed in this way, since the said surfaces are located in close proximity to the blades of the propeller screw.

I have not attempted to explain all of the minute details of the construction of the combined rudder and propeller frame, for it will be understood by those to whom this specification is addressed that the parts will be of the proper size and relationship and will be properly mounted, connected and supported according to\the tenets of naval architecture.

W'hat I claim is 1. A rudder arrangement for ships comprising in combination" a post supporting a propeller shaft, a rudder post connected with said first mentioned post to form a closed frame, a balanced rudder having a stream line form enclosing said rudder post, and a rudder shaft rotatably mounted in said closed frame and connected with the rudder.

2. A rudder arrangement for ships comprising in combinatlon a post supporting a propeller shaft, a rudder post connected with said first mentioned post to form a closed frame, a balanced rudder having a stream line form enclosing said rudder post,

and a rudder shaft rotatably mounted in said closed frame and connected with the rudder, the axis of rotation. of said rudder shaft substantially coinciding with that of the rudder post.

3. A rudder arrangement for ships comprising in combination a post supporting a propeller shaft, a rudder post. connected with said first mentioned post to form a closed frame, a balanced rudder having a stream line form enclosing said rudder ost, said rudder consisting of two detacha ly interconnected parts, and a rudder shaft rotatably mounted in said closed frame and connected with the rudder.

4. A rudder arrangement for ships comprising in combination a post supporting a propeller shaft, a rudder post connected with said first mentioned post to form a closed frame, a balanced rudder having a stream line form enclosing said rudder post, said rudder consisting of two detachably interconnected parts, and a rudder shaft rotatably mounted in the aforesaid closed frame and connected with the rudder, the axis of rotation of said rudder shaft substantially coinciding with the rudder post.

5. A rudder arran ement for ships comprising in combination a post supporting the propeller shaft, a rudder post connected with said first mentioned post to form a closed frame, a balanced rudder having a stream line form enclosing said rudder post and consisting of two dctachably interconnected parts, said parts comprising an aft part and a fore art, and a rudder shaft rotatably mounte in said closed frame and connected with the rudder.

6. A rudder arrangement for ships comprising in combination a post supporting the propeller shaft, a rudder post connected with said first mentioned post to form a closed frame, a balanced rudder having a stream line form enclosing said rudder post, the two lateral surfaces of the rudder body being differently shaped for the purpose of guiding the water displaced by thepropeller, the upper part of the body having the same shape as the lower art of the body, the angle of said surfaces ing oppositely formed with respect to the longitudinal axis ofthe rudder, and a rudder shaft rotatably mounted in the aforesaid closed frame and connected with the rudder.

In testimony whereof I aflix herebelow my signature.

HANS HASS. 

